CN108621123B

CN108621123B - Passive compliance mechanism

Info

Publication number: CN108621123B
Application number: CN201710176748.0A
Authority: CN
Inventors: 米夏埃尔·施维勒; 彭志诚; 鲍朝安; 易子民; 朱威颖
Original assignee: Delta Electronics Inc
Current assignee: Delta Electronics Inc
Priority date: 2017-03-23
Filing date: 2017-03-23
Publication date: 2020-09-08
Anticipated expiration: 2037-03-23
Also published as: CN108621123A

Abstract

The invention provides a passive compliance mechanism. The passive compliance mechanism includes a fixed end, a base, and a stiffness adjustment assembly. The base is arranged on the fixed end and comprises two grooves and a sheet-shaped elastic body, the first end of the sheet-shaped elastic body is connected with the base, and the second end of the sheet-shaped elastic body is adjacent to the outer side part of the fixed end; the rigidity adjustment assembly comprises a linear slide rail, a sliding block and two stop blocks. The linear slide rail is arranged on the fixed end; the sliding block is movably arranged on the linear sliding rail; the two stop blocks are fixedly arranged on the sliding block and move synchronously with the sliding block, are attached to two sides of the flaky elastic body to mutually clamp the flaky elastic body, and adjust the rigidity of the base through the change of the clamping position.

Description

Passive compliance mechanism

Technical Field

The present invention relates to a passive compliance mechanism, and more particularly, to a passive compliance mechanism with adjustable rigidity.

Background

With the development of science and technology, robots have been widely used in various fields, thereby increasing the production speed and reducing the labor cost. In order to respond to the flexible action required by the assembly process, the robot, such as a service robot, with the lifting part directly contacting with the user, has safety in use, and a compliance mechanism is conveniently arranged in the robot so as to enable the robot to have compliance. The compliance mechanism can be divided into an active compliance mechanism and a passive compliance mechanism, wherein the passive compliance mechanism achieves compliance by absorbing energy or generating flexible motion, so that the response time can be faster, and the passive compliance mechanism is generally applied to various robots.

Generally, the conventional passive compliance mechanism utilizes the elastic force of a spring to achieve the compliance effect. However, the spring coefficient of the spring used to achieve the compliance function in the conventional passive compliance mechanism is fixed, which results in the fixed rigidity of the passive compliance mechanism and thus the non-adjustable rigidity, so that once the passive compliance mechanism is applied to different working environments or different robots, and further needs to adjust the rigidity correspondingly, the conventional passive compliance mechanism can only meet the requirements by replacing the spring or redesigning the passive compliance mechanism, which results in the problems of poor applicability and increased cost of the conventional passive compliance mechanism.

Therefore, there is a need for a passive compliance mechanism that can improve the above-mentioned drawbacks of the prior art.

Disclosure of Invention

The present invention is directed to a passive compliance mechanism, which solves the problem of poor applicability and cost increase due to the fact that the passive compliance mechanism is provided with a spring to generate passive compliance, and the rigidity of the passive compliance mechanism is fixed and cannot be adjusted.

To achieve the above objective, a preferred embodiment of the present invention is a passive compliance mechanism, which includes a fixing end, a base and a stiffness adjusting assembly. The base is arranged on the fixed end and comprises two grooves and a sheet-shaped elastic body. The two grooves are arranged adjacently, the sheet-shaped elastic body is arranged between the two grooves and extends from the base to the outer side part of the fixed end, the first end of the sheet-shaped elastic body is connected with the base, and the second end of the sheet-shaped elastic body is adjacent to the outer side part of the fixed end; the rigidity adjustment assembly is arranged on the fixed end and comprises a linear slide rail, a sliding block and two stop blocks. The linear slide rail is arranged on the fixed end and corresponds to the extending direction of the sheet-shaped elastic body; the sliding block is movably arranged on the linear sliding rail; the two stop blocks are fixedly arranged on the sliding block and move synchronously with the sliding block, and are respectively attached to the two opposite sides of the flaky elastic body to mutually clamp the flaky elastic body so as to adjust the rigidity of the base through the position change of the clamped flaky elastic body.

To achieve the above objective, another preferred embodiment of the present invention is a passive compliance mechanism, which includes a fixing end, a base, a first stiffness adjusting assembly, and a stiffness switching module. The base is arranged on the fixed end and comprises a first groove, a second groove and a sheet-shaped elastic body. The flaky elastic body is arranged on the base, arranged in the first groove and extended from the side edge of the base to the outer side part of the fixed end, the first end of the flaky elastic body is connected with the base, and the second end of the flaky elastic body is adjacent to the outer side part of the fixed end; the first rigidity adjusting assembly is arranged on the fixed end and comprises a first linear sliding rail, a first sliding block and two first stop blocks. The first linear slide rail is arranged on the fixed end and corresponds to the extending direction of the sheet-shaped elastic body; the first sliding block is movably arranged on the first linear sliding rail; the two first stop blocks are fixedly arranged on the first sliding block and move synchronously with the first sliding block, and are respectively attached to two opposite sides of the flaky elastic body to mutually clamp the flaky elastic body so as to adjust the rigidity of the base through the position change of the clamped flaky elastic body; the rigidity switching module is arranged on the fixed end and comprises a second linear sliding rail, a second sliding block and a second stop block. The second linear sliding rail is arranged on the fixed end; the second sliding block is movably arranged on the second linear sliding rail and moves to a first position or a second position; the second stop block is fixedly arranged on the second sliding block and moves synchronously with the second sliding block; the first position is that the second sliding block drives the second stop block to move into the groove and abut against and be clamped in the groove, so that the base is maintained at the position with the maximum rigidity, and the second position is that the second sliding block drives the second stop block to move to the position separated from the groove.

The passive compliance mechanism provided by the invention has the advantages and beneficial effects that:

the invention discloses a passive compliance mechanism, which can adjust the rigidity of a base through a rigidity adjusting component without replacing any element or changing the design, so that the passive compliance mechanism can generate different degrees of compliance and is further suitable for robots with different requirements and types. In addition, the passive compliance mechanism of the present invention can be provided with a plurality of stiffness adjustment assemblies, so that the stiffness adjustment is more flexible and precise. Moreover, the wire rods required by the passive compliance mechanism can realize hollow wiring by utilizing the hollow channel, thereby achieving the effect of simplifying wiring. In addition, the passive compliance mechanism of the present invention can be provided with a sensor to measure the displacement or angle of the base relative to the fixed end caused by the elastic deformation, and further the torsion value of the passive compliance mechanism can be calculated by using the measurement result and the information of the rigidity of the base.

Drawings

Fig. 1 is a schematic perspective view of a passive compliance mechanism according to a first embodiment of the present invention.

Fig. 2 is a schematic perspective view of a variation of the passive compliance mechanism of the first embodiment of the present invention shown in fig. 1.

Fig. 3 is a schematic perspective view of a passive compliance mechanism according to a second embodiment of the present invention.

Fig. 4 is a top view of the passive compliance mechanism of the second embodiment of the present invention shown in fig. 3.

Fig. 5 is a schematic perspective view of a variation of the passive compliance mechanism of the second embodiment of the present invention shown in fig. 3.

Fig. 6 is a top view of another variation of the passive compliance mechanism of the second embodiment of the present invention shown in fig. 3.

Description of reference numerals:

10. 10 ', 20', 20 ": passive compliance mechanism

11. 21: fixed end

111: sleeving part

12. 22: base seat

121: groove

122. 222: sheet-like elastic body

123: trepan boring

224: the first groove

221: second groove

13: rigidity adjustment assembly

131: linear sliding rail

132: sliding block

133: stop block

134: stopper

135: stop part

14: sensor device

15: motor with a stator having a stator core

16: cable wire

17: electromagnetic drive module

23: first rigidity adjustment assembly

231: first linear slide rail

232: first sliding block

233: first stop block

24: rigid switching module

241: second linear slide rail

242: second slider

243: second stop block

19. 29: hollow channel

Detailed Description

Some exemplary embodiments that embody features and advantages of the invention will be described in detail in the description that follows. It is to be understood that the invention is capable of various modifications in various embodiments without departing from the scope of the invention, and that the specification and drawings are to be regarded as illustrative in nature, and not as restrictive.

Please refer to fig. 1, which is a schematic perspective view of a passive compliance mechanism according to a first preferred embodiment of the present invention. As shown in fig. 1, the passive compliance mechanism 10 is suitable for various robots, such as a service robot, a cooperative robot, or an industrial robot, and is assembled in joints of arms or feet of the robot, and includes a fixing end 11, a base 12, and a stiffness adjusting assembly 13.

The fixed end 11 can be assembled on the joint of the robot. The base 12 is disposed on the fixed end 11 through a bearing (not shown), and is made of a flexible material, when the base 12 is acted by an external force, the base 12 will generate a corresponding degree of elastic deformation according to the rigidity of the base 12, so that the base 12 will displace relative to the fixed end 11, whereby the base 12 can provide a compliance function, and the base 12 includes two grooves 121 and a sheet-shaped elastic body 122. The two grooves 121 are disposed adjacently, and each groove 121 is formed by recessing the outer side of the base 12 toward the center. The sheet-like elastic body 122 is disposed between the two grooves 121 and extends from the base 12 toward the outer side of the fixed end 11, wherein a first end of the sheet-like elastic body 122 is connected to the base 12, and a second end of the sheet-like elastic body 122 is adjacent to the outer side of the fixed end 11. In some embodiments, the base 12 and the sheet-like elastic body 122 may be integrally formed.

The rigid adjusting component 13 is disposed on the fixing end 11 and includes a linear sliding rail 131, a sliding block 132 and two stoppers 133. The linear slide rail 131 is disposed on the fixed end 11 and corresponds to the extending direction of the sheet-shaped elastic body 122. The sliding block 132 is movably disposed on the linear guideway 131. The two stoppers 133 are fixed on the sliding block 132 and driven by the sliding block 132 to move synchronously with the sliding block 132, and the two stoppers 133 are respectively attached to two opposite sides of the sheet-shaped elastic body 122 to clamp the sheet-shaped elastic body 122, so that the rigidity of the base 12 is adjusted by changing the position at which the two stoppers 133 clamp the sheet-shaped elastic body 122. As can be seen from the above, the two grooves 121, the sheet-shaped elastic body 122 and the rigidity adjusting component 13 are actually matched with each other to form a first rigidity adjusting module, so as to adjust the rigidity of the base 12.

In the above embodiment, the size and shape of the two grooves 121 may be, but not limited to, the size and shape corresponding to the two stoppers 133, and the two stoppers 133 are formed by recessing the outer portion of the base 12 toward the center, so as to make the two stoppers 133 engage with each other. In addition, when the sliding block 132 drives the two stoppers 133 to move into the two grooves 121 and abut against and engage with the two grooves 121 respectively, the base 12 is maintained at the maximum rigidity, and if the base 12 is subjected to an external force, the two stoppers 133 cannot elastically deform because of abutting against and engaging with the two grooves 121 respectively, so that the base 12 is indirectly fixed on the fixing end 11, in other words, the base 12 cannot elastically deform relative to the fixing end 11, and therefore the base 12 can achieve the maximum rigidity similar to the structural rigidity of the fixing end 11. In addition, when the sliding block 132 drives the two stoppers 133 to disengage from the two grooves 121 without abutting against and engaging with the two grooves 121, and move between the first end and the second end of the sheet-shaped elastic body 122, the position where the two stoppers 133 are clamped on the sheet-shaped elastic body 122 can be correspondingly changed, and the distance between the clamped position of the sheet-shaped elastic body 122 and the first end of the sheet-shaped elastic body 122 actually affects the actual length of the sheet-shaped elastic body 122, and further affects the rigidity of the base 12, so that the rigidity of the base 12 can be adjusted by changing the position where the two stoppers 133 are clamped on the sheet-shaped elastic body 122, in this embodiment, when the position where the two stoppers 133 are clamped on the sheet-shaped elastic body 122 by the driving of the sliding block 132 is closer to the second end, the rigidity of the base 12 is smaller, otherwise, when the position where the two stoppers 133 are clamped on the sheet-shaped elastic body 122 by the driving of, the more rigid the base 12.

As can be seen from the above, the passive compliance mechanism 10 of the present invention utilizes the flexible (elastic) base 12 to absorb the impact force, so that the passive compliance mechanism 10 of the present invention and the robot to which the same is applied have compliance. In addition, the rigidity of the base 12 of the present invention can be further adjusted by the rigidity adjusting component 13, so as to adjust the passive compliance mechanism 10 to have different degrees of compliance, and thus, the passive compliance mechanism 10 of the present invention can be adapted to robots with different requirements and types without replacing any components or changing the design, for example, the base 12 can be adjusted to have the maximum rigidity to be adapted to an industrial robot requiring high rigidity, can be adjusted to have a smaller rigidity and a greater degree of compliance to be adapted to a service robot, or a cooperative robot that needs to work together with an operator, so that the passive compliance mechanism 10 of the present invention has better applicability and can reduce the cost.

In some embodiments, the heights of the sheet-like elastic bodies 122 disposed on the passive compliance mechanism 10 of the present invention from the first end to the second end may be the same, however, in order to make the two stoppers 133 clamped at different positions of the sheet-like elastic body 122 by the driving of the sliding block 132, the stiffness adjustment ratio of the base 12 is more obvious and the adjustable range is larger, so as to make the stiffness adjustment more effective, in the preferred embodiment of the present invention, as shown in fig. 1, the heights of the sheet-like elastic bodies 122 may decrease in a direction from the first end to the second end.

Referring again to fig. 1, the passive compliance mechanism 10 of the present invention further includes a cable 16 and a motor 15. The cable 16 is connected between the motor 15 and the slider 132. The motor 15 is used to drive the cable 16, so that the cable 16 pulls the sliding block 132 to move on the linear guideway 131. Of course, the method of driving the slide block 132 to move on the linear slide 131 is not limited to this, and a driving method such as electromagnetic induction may be used.

In addition, the fixing end 11 further includes a sleeve portion 111. The base 12 further includes a sleeve hole 123 disposed at a position corresponding to the sleeve portion 111 for the sleeve portion 111 to pass through, so that the base 12 is disposed on the fixing end 11. The passive compliance mechanism 10 further includes a hollow channel 19, and the hollow channel 19 is formed by a hollow portion of the fixing end 11 and a hollow portion of the sheathing portion 111 being communicated with each other, so that wires, such as the cable 16, required to be used in the passive compliance mechanism 10 of the present invention can be accommodated in the hollow channel 19, so as to simplify the routing by using a hollow routing manner, and prevent the wires from being damaged due to the operation of the passive compliance mechanism 10.

In addition, in some embodiments, the rigidity adjustment assembly 13 may further include two stoppers 134 disposed on the fixed end 11 at intervals, wherein one stopper 134 is adjacent to the center of the fixed end 11, the other stopper 134 is adjacent to the outer side of the fixed end 11, a moving space is formed between the two stoppers 134, and the length of the moving space is substantially greater than or equal to a distance between a position where the two stoppers 133 move into the two grooves 121 to respectively abut against and engage with the two grooves 121 and a position where the two stoppers 133 move to clamp the second end of the sheet-shaped elastic body 122. In addition, the sliding block 132 further includes a stopping portion 135, which extends from one side of the sliding block 132, and is partially located in the moving space formed between the two stoppers 134, when the sliding block 132 moves on the linear slide rail 131, the stopping portion 135 of the sliding block 132 can be limited to move only in the moving space by the two stoppers 134 and the stopping portion 135 abutting against each other, so that when the two stoppers 133 are driven by the sliding block 132 to move into the two grooves 121 and abut against and engage with the two grooves 121, respectively, the sliding block 132 cannot move continuously toward the center of the fixed end 11, and when the two stoppers 133 are driven by the sliding block 132 to move to the second end clamped in the sheet-shaped elastic body 122, the sliding block 132 cannot move continuously toward the outer side of the fixed end 11.

In addition, in some embodiments, the passive compliance mechanism 10 of the present invention may include a sensor 14 disposed on the fixing end 11 corresponding to the base 12 for measuring a displacement of the base 12 relative to the fixing end 11 caused by the elastic deformation. Therefore, given the rigidity of the base 12, the amount of displacement sensed by the sensor 14 can be used to calculate the torque applied to the passive compliance mechanism 10, thereby achieving the torque sensing function. Of course, the sensor 14 is not limited to measuring the displacement of the base 12 relative to the fixed end 11 caused by the elastic deformation, but can also measure the twist angle of the base 12 relative to the fixed end 11 caused by the elastic deformation, so as to achieve the function of torque sensing.

In addition, in order to make the passive compliance mechanism of the present invention more flexible in adjusting rigidity and improve the accuracy of adjusting rigidity, in some embodiments, as shown in fig. 2, the passive compliance mechanism 10' further includes a second rigidity adjustment module, the components, connection and functions of the second rigidity adjustment module are similar to those of the first rigidity adjustment module shown in fig. 1, that is, the second rigidity adjustment module and the first rigidity adjustment module are respectively disposed on two opposite sides of the fixed end 11, i.e. the second rigidity adjustment module also includes two grooves 121, the sheet-shaped elastic body 122 and the rigidity adjustment component 13, so the detailed description about the components and the operation are omitted herein, but not limited thereto, the second rigidity adjustment module may also be disposed adjacent to the first rigidity adjustment module, by additionally providing the second rigidity adjustment module, the first rigidity adjustment module and the second rigidity adjustment module can be matched with each other to adjust the rigidity of the base 12. In other embodiments, more than three sets of rigidity adjustment modules may be further provided according to actual requirements.

Referring to fig. 3 and 4, fig. 3 is a schematic perspective view of a passive compliance mechanism according to a second preferred embodiment of the present invention, and fig. 4 is a top view of the passive compliance mechanism shown in fig. 3. As shown, the passive compliance mechanism 20 can be applied to various robots such as service robots, cooperative robots, and industrial robots, and is assembled in joints of arms or feet of the robots, and includes a fixing end 21, a base 22, a first rigidity adjusting component 23, and a rigidity switching module 24.

The fixed end 21 can be assembled on the joint of the robot. The base 22 is disposed on the fixed end 21 through a bearing (not shown), and is made of a flexible material, when the base 22 is subjected to an external force, the base 22 will generate a corresponding degree of elastic deformation according to the rigidity of the base 22, so that the base 22 will displace relative to the fixed end 21, and thereby the base 22 can provide a compliance function, and the base 22 includes a first groove 224, a second groove 221 and a sheet-shaped elastic body 222. The second groove 221 may be, but not limited to, a fan-shaped structure, and is formed by recessing the outer side of the base 22 toward the center. The sheet-like elastic body 222 is assembled on the base 22 and disposed in the first groove 224, and extends from the side of the base 22 to the outer side of the fixed end 21, and a first end of the sheet-like elastic body 222 is connected to the base 22, and a second end of the sheet-like elastic body 222 is adjacent to the outer side of the fixed end 21. In the present embodiment, the sheet-shaped elastic body 222 is alternatively assembled on the base 22, but not limited thereto, and the sheet-shaped elastic body 222 and the base 22 may also be integrally formed. Further, the sheet-shaped elastic body 222 may divide the first groove 224 into two area spaces. Furthermore, the second groove 221 and the first groove 224 are oppositely disposed on the base 22.

The first rigid adjusting component 23 is disposed on the fixing end 21 and includes a first linear slide rail 231, a first slide block 232 and two first stoppers 233. The first linear slide rail 231 is disposed on the fixed end 21 and corresponds to the extending direction of the sheet-shaped elastic body 222. The first sliding block 232 is movably disposed on the first linear sliding rail 231. The two first stoppers 233 are fixedly disposed on the first sliding block 232 and can be driven by the first sliding block 232 to move synchronously with the first sliding block 232, and the two first stoppers 233 are respectively attached to two opposite sides of the sheet-shaped elastic body 222 to clamp the sheet-shaped elastic body 222, and the rigidity of the base 22 is adjusted by changing the position between the first end and the second end of the sheet-shaped elastic body 222 clamped by the two first stoppers 233. Since the distance between the clamped position of the sheet-shaped elastic body 222 and the first end of the sheet-shaped elastic body 222 actually affects the actual length of the sheet-shaped elastic body 222 and further affects the rigidity of the base 22, the rigidity of the base 22 can be adjusted by changing the position at which the two first stoppers 233 are clamped on the sheet-shaped elastic body 222, in this embodiment, the rigidity of the base 22 is smaller when the two first stoppers 233 are closer to the second end of the sheet-shaped elastic body 222, and conversely, the rigidity of the base 22 is larger when the two first stoppers 233 are closer to the first end of the sheet-shaped elastic body 222 through the first sliding blocks 232. In addition, when the two first stoppers 233 get closer to the first end of the sheet-shaped elastic body 222 through the first sliding block 232, the two first stoppers 233 will be respectively received in the corresponding area spaces separated by the first groove 224 by the sheet-shaped elastic body 222. In addition, the first groove 224, the sheet-shaped elastic body 222 and the first rigidity adjustment component 23 are actually matched with each other to form a first rigidity adjustment module, so as to adjust the rigidity of the base 22.

The rigid switch module 24 is disposed on the fixing end 21 corresponding to the second groove 221, and includes a second linear slide rail 241, a second slide block 242, and a second stop 243. The second linear sliding rail 241 is disposed on the fixed end 21 corresponding to the second groove 221. The second sliding block 242 is movably disposed on the second linear sliding rail 241 and can move to a first position or a second position. The second stop 243 is fixed on the second sliding block 242 and moves synchronously with the second sliding block 242.

In the above embodiment, the first position is that the second sliding block 242 drives the second stopper 243 to move into the second groove 221 to abut against and engage with the second groove 221, so that the base 22 is maintained at the position of maximum rigidity, at this time, if the base 22 is subjected to an external force, the second stopper 243 abuts against and engages with the second groove 221, and cannot generate elastic deformation, so that the base 22 is indirectly fixed on the fixing end 21, in other words, the base 22 cannot generate elastic deformation relative to the fixing end 21, so that the base 22 can achieve the maximum rigidity similar to the structural rigidity of the fixing end 21, and the second position is that the second sliding block 242 drives the second stopper 243 to move to the position completely separated from the second groove 221.

As can be seen from the above, when the rigidity of the base 22 needs to be the maximum rigidity, the passive compliance mechanism 20 of the embodiment can move the second sliding block 242 to the first position to move the second stopper 243 into the second groove 221 to abut against and engage with the second groove 221, whereas when the rigidity of the base 22 needs to be dynamically adjusted, the second sliding block 242 can move to the second position, and the rigidity of the base 22 can be adjusted by changing the positions at which the two first stoppers 233 clamp the sheet-shaped elastic body 222.

In this embodiment, the passive compliance mechanism 20 further includes an electromagnetic driving module 17 disposed on the fixing end 21 and adjacent to the first sliding block 232, and the electromagnetic driving module 17 drives the first sliding block 232 to move on the first linear sliding rail 231 by an electromagnetic induction method. Of course, the way of driving the first sliding block 232 to move on the first linear sliding rail 231 is not limited thereto, and for example, a similar way to the way of driving the cable 16 by the motor 15 disclosed in fig. 1 to pull the sliding block 132 to move on the linear sliding rail 131 can be used. Similarly, the rigid switch module 24 in the passive compliance mechanism 20 can also move the second sliding block 242 on the second linear sliding rail 241 by using the above-mentioned various driving methods. In addition, the passive compliance mechanism 20 further includes a hollow channel 29, and the hollow channel 29 penetrates through the fixing end 21 and the base 22, so that the wires required to be used in the passive compliance mechanism 20 of the present invention can be accommodated in the hollow channel 29, so as to simplify the wiring by using the hollow wiring manner, and simultaneously prevent the wires from being damaged due to the operation of the passive compliance mechanism 20.

In this embodiment, the heights of the sheet-like elastic bodies 222 disposed on the passive compliance mechanism 20 are the same from the first end to the second end, however, in order to make the two first stoppers 233 clamped at different positions of the sheet-like elastic body 222 by the driving of the sliding block 232, the stiffness of the base 12 can be adjusted more significantly and within a wider adjustable range, so that the stiffness adjustment effect is better, in some embodiments, as shown in fig. 5, the heights of the sheet-like elastic bodies 222 'of the passive compliance mechanism 20' can decrease along the direction from the first end to the second end.

In order to make the passive compliance mechanism of the present invention more flexible in adjusting the stiffness and improve the accuracy of adjusting the stiffness, in some embodiments, as shown in fig. 6, the passive compliance mechanism 20 ″ further includes a second stiffness adjusting module, which has components, connection relationships, and functions similar to those of the first stiffness adjusting module shown in fig. 4, that is, the second stiffness adjusting module also includes the first groove 224, the sheet-shaped elastic body 222, and the first stiffness adjusting component 23, so that the relationship and the operation of the components are not repeated herein, the second stiffness adjusting module may be disposed adjacent to the first stiffness adjusting module, but is not limited thereto, and the second stiffness adjusting module and the first stiffness adjusting module may also be disposed on two opposite sides of the fixing end 21. By additionally providing the second rigidity adjustment module, the first rigidity adjustment module and the second rigidity adjustment module can be matched with each other to adjust the rigidity of the base 22. In other embodiments, more than three sets of rigidity adjustment modules may be further provided according to actual requirements.

In summary, the present invention discloses a passive compliance mechanism, wherein the passive compliance mechanism can adjust the rigidity of the base through the rigidity adjustment component without replacing any component or changing the design, so as to generate different degrees of compliance for the passive compliance mechanism, and further suitable for robots with different requirements and types, for example, the base can be adjusted to have the maximum rigidity to be suitable for industrial robots requiring high rigidity, and can also be adjusted to have smaller rigidity and greater degree of compliance to be suitable for service robots, or cooperative robots that need to work together with the operator, so that the adaptability is better and the cost can be reduced. In addition, the passive compliance mechanism of the present invention can be provided with a plurality of stiffness adjustment assemblies, so that the stiffness adjustment is more flexible and precise. Moreover, the wire rods required by the passive compliance mechanism can realize hollow wiring by utilizing the hollow channel, thereby achieving the effect of simplifying wiring. In addition, the passive compliance mechanism of the present invention can be provided with a sensor to measure the displacement or angle of the base relative to the fixed end caused by the elastic deformation, and further the torsion value of the passive compliance mechanism can be calculated by using the measurement result and the information of the rigidity of the base.

It should be noted that the above-mentioned embodiments illustrate only preferred embodiments of the invention, and that the invention is not limited to the specific embodiments described, except as indicated by the appended claims. And that the invention may be modified or varied by those skilled in the art without departing from the scope of the claims.

Claims

1. A passive compliance mechanism, comprising:

a fixed end;

a base, arranged on the fixed end and comprising two grooves and a sheet-shaped elastomer, wherein the two grooves are arranged adjacently, the sheet-shaped elastomer is arranged between the two grooves and extends from the base to the outer side part of the fixed end, a first end of the sheet-shaped elastomer is connected with the base, and a second end of the sheet-shaped elastomer is adjacent to the outer side part of the fixed end; and

a rigidity adjustment assembly disposed on the fixed end, comprising:

a linear slide rail arranged on the fixed end and corresponding to the extending direction of the sheet-shaped elastic body;

a sliding block movably arranged on the linear slide rail; and

two stop blocks which are fixedly arranged on the sliding block and move synchronously with the sliding block, are respectively attached to two opposite sides of the flaky elastic body to mutually clamp the flaky elastic body and are used for adjusting the rigidity of the base through the position change of clamping the flaky elastic body;

when the sliding block drives the two stop blocks to move into the two grooves and respectively abut against and are clamped in the two grooves, the base is maintained at the maximum rigidity.

2. The passive compliance mechanism of claim 1, wherein the base is more rigid when the two stoppers are clamped to the sheet-like elastic body closer to the first end, and the base is less rigid when the two stoppers are clamped to the sheet-like elastic body closer to the second end.

3. The passive compliance mechanism of claim 1, wherein the sheet-like elastomer is integrally formed with the base.

4. The passive compliance mechanism of claim 1, wherein the height of the sheet-like elastic body decreases from the first end toward the second end.

5. The passive compliance mechanism as claimed in claim 1, wherein the passive compliance mechanism further comprises a cable connected between a motor and the slider, and driven by the motor to pull the slider to move on the linear guideway.

6. The passive compliance mechanism of claim 1, wherein the fixed end further comprises a receiving portion and the base further comprises a receiving hole for the receiving portion to pass through so that the base is disposed on the fixed end.

7. The passive compliance mechanism of claim 6, wherein the passive compliance mechanism further comprises a hollow channel formed by a hollow portion of the fixing end and a hollow portion of the engaging portion communicating with each other.

8. The passive compliance mechanism of claim 1, further comprising a sensor disposed on the fixed end corresponding to the base for measuring a displacement or a twist angle of the base relative to the fixed end due to elastic deformation.

9. The passive compliance mechanism of claim 1, wherein two of the grooves, the sheet-like elastic body and the stiffness adjustment assembly form a first stiffness adjustment module, and further comprising a second stiffness adjustment module having a structure identical to that of the first stiffness adjustment module, the first and second stiffness adjustment modules being disposed on opposite sides of the fixed end, the first and second stiffness adjustment modules cooperating with each other to adjust the stiffness of the base.

10. The passive compliance mechanism as claimed in claim 1, wherein the stiffness adjustment assembly further comprises two stoppers disposed at intervals on the fixed end, one of the stoppers is adjacent to a center of the fixed end, the other stopper is adjacent to an outer side of the fixed end, and a moving space is formed between the two stoppers.

11. The passive compliance mechanism of claim 10, wherein the sliding block further comprises a stop portion extending from one side of the sliding block and partially located in the moving space, the stop portion limiting the moving range of the sliding block by the two stoppers.

12. The passive compliance mechanism of claim 11, wherein the length of the movement space is substantially greater than or equal to a distance between a position where the two stoppers move into the two grooves to abut against and engage with the two grooves and a position where the two stoppers move to hold the second end.

13. A passive compliance mechanism, comprising:

a fixed end;

a base, disposed on the fixed end, and including a first groove, a second groove and a sheet-like elastic body, the sheet-like elastic body being disposed on the base and in the first groove, and extending from the side of the base toward the outer side of the fixed end, and a first end of the sheet-like elastic body being connected to the base, and a second end of the sheet-like elastic body being adjacent to the outer side of the fixed end;

a first rigidity adjustment assembly disposed on the fixed end, comprising:

the first linear sliding rail is arranged on the fixed end and corresponds to the extending direction of the sheet-shaped elastic body;

a first sliding block movably arranged on the first linear sliding rail; and

two first stop blocks which are fixedly arranged on the first sliding block and move synchronously with the first sliding block, are respectively attached to two opposite sides of the flaky elastic body to mutually clamp the flaky elastic body and are used for adjusting the rigidity of the base through the position change of clamping the flaky elastic body; and

a rigid switching module, arranged on the fixed end, comprising;

the second linear sliding rail is arranged on the fixed end;

a second sliding block movably arranged on the second linear sliding rail and moved to a first position or a second position; and

the second stop block is fixedly arranged on the second sliding block and moves synchronously with the second sliding block;

the first position is that the second sliding block drives the second stop block to move into the second groove and abut against and be clamped in the second groove, so that the base is maintained at a position with maximum rigidity, and the second position is that the second sliding block drives the second stop block to move to a position separated from the second groove.

14. The passive compliance mechanism of claim 13, wherein when the second slider block moves to the second position, the stiffness of the base is greater the closer the two stoppers are clamped to the sheet-like elastic body to the first end, and the stiffness of the base is less the closer the two stoppers are clamped to the sheet-like elastic body to the second end.

15. The passive compliance mechanism of claim 13, wherein the sheet-like elastomer is replaceably disposed on the base.

16. The passive compliance mechanism of claim 13, wherein the height of the sheet-like elastic body decreases from the first end toward the second end.

17. The passive compliance mechanism of claim 13, further comprising an electromagnetic driving module disposed on the fixed end and adjacent to the first slider, wherein the electromagnetic driving module drives the first slider to move on the first linear guide by electromagnetic induction.

18. The passive compliance mechanism of claim 13, wherein the passive compliance mechanism further comprises a hollow channel extending through the fixed end and the base.

19. The passive compliance mechanism of claim 13, wherein the first recess, the sheet-like elastic body and the first stiffness adjustment assembly form a first stiffness adjustment module, and further comprising a second stiffness adjustment module having a structure identical to that of the first stiffness adjustment module, the first stiffness adjustment module and the second stiffness adjustment module being disposed adjacent to each other, the first stiffness adjustment module and the second stiffness adjustment module cooperating with each other to adjust the stiffness of the base.